{"id":"F2006B02783","name":"AD/B727/8 - Horizontal Stabilizer Trailing Edge Lower Beam and Elevator","slug":"ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42125,"registerId":"commonwealth-F2006B02783-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/8 - Horizontal Stabilizer Trailing Edge Lower Beam and Elevator","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Boeing 727 Series Aeroplanes\n\n \n\nAD/B727/8 Horizontal Stabilizer Trailing Edge Lower Beam and Elevator\n\nApplicability: As per requirement document. Document: Boeing SB No. 55-15B. Compliance: Forthwith.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n\n11/65\n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1965 addressing a specific structural component on one aircraft type. It has not expanded beyond its original scope; it remains a targeted safety mandate for the Boeing 727 horizontal stabilizer."},"complexity_factors":["Extremely short document (approximately 150 words)","No defined terms section — relies entirely on external reference to Boeing Service Bulletin 55-15B","No conditional logic or nested exceptions","Single, unambiguous compliance requirement ('Forthwith')","Minimal cross-referencing (only to the Boeing SB and Civil Aviation Regulations Part 39)","Clear applicability statement referencing external document"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998.\n\n**What it does:**\nThis directive requires owners and operators of **Boeing 727 series aircraft** to take immediate action regarding a specific structural component: the **horizontal stabilizer trailing edge lower beam and elevator**. These are parts of the aircraft's tail assembly that control pitch (up and down movement).\n\n**Who it affects:**\n- Operators of Boeing 727 aircraft registered in Australia\n- Maintenance organisations servicing these aircraft\n\n**What must be done:**\nThe directive references **Boeing Service Bulletin No. 55-15B** — a technical document issued by the manufacturer detailing the required inspection or repair procedure. Operators must follow this document \"**forthwith**\" (immediately, without delay).\n\n**Why it matters:**\nAirworthiness Directives are legally enforceable safety mandates. They typically issue when a safety defect, design flaw, or maintenance issue has been identified that could affect flight safety. Non-compliance can ground an aircraft and result in penalties. This particular AD dates from November 1965 (\"11/65\"), indicating it addresses a long-standing structural concern with this aircraft type."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD text does not indicate any amendment or change to a prior instrument or original intent. It imposes requirements by reference to Boeing SB No. 55-15B and requires compliance immediately. To determine whether the practical scope has changed relative to any earlier directive would require comparison with prior documents, which are not included in the AD text provided."},"complexity_factors":["Very short AD text that delegates technical scope and affected serial numbers to an external Boeing service bulletin (increases reliance on external document for full scope).","Immediate compliance timeline (\"Forthwith\") creates operational urgency and potential scheduling complexity for operators.","No technical detail, rationale, or exemptions included in the AD itself (forces cross-reference and possible follow-up with regulator or manufacturer).","Clear regulatory authority and mandatory nature reduce legal ambiguity, but practical implications depend entirely on the content of Boeing SB No. 55-15B."],"plain_english_summary":"This Airworthiness Directive forces operators of affected Boeing 727s to comply immediately with Boeing Service Bulletin No. 55-15B, as mandated by CASA. It makes the service bulletin’s technical instructions compulsory (“Forthwith”), so owners and maintenance organisations must carry out and pay for the required work or inspections. The AD itself delegates technical scope, affected serials and methods to the referenced Boeing document, so consult SB 55-15B for details."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator","history":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator/history","analysis":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator/analysis","conflicts":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator/conflicts","importantCases":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator/important-cases","documents":"/api/acts/ad-b727-8-horizontal-stabilizer-trailing-edge-lower-beam-and-elevator/documents"}}